Personally, I'm waiting for the "put rocket boosters on Mars and fling it into Venus, re-enacting the impact that created the Moon and altering Venus's orbit to

Personally, I'm waiting for the "put rocket boosters on Mars and fling it into Venus, re-enacting the impact that created the Moon and altering Venus's orbit to be approximately opposite of Earth's (but still safely far away), thus creating Earth-2" mission.